1. Field of the Invention
The present invention relates to a torque limiting device, particularly to a torque limiting device for a fishing reel, which is configured to limit torque between a rotatable shaft member and a rotary member disposed on the outer peripheral side of the shaft member in the fishing reel.
2. Background Art
The dual-bearing reels are provided with a fishing-line guide device, which is so-called a level winding mechanism. The level winding mechanism includes a driven gear (an exemplary rotary member), a traverse cam shaft and a fishing-line guide. The driven gear is a member to which rotation of a handle shaft is transmitted. The traverse cam shaft is configured to be unitarily rotated with the driven gear. The fishing-line guide is configured to be axially reciprocated while being meshed with the traverse cam shaft. The traverse cam shaft has intersecting helical grooves on the outer peripheral surface thereof. The fishing-line guide includes an engaging member to be engaged with the helical grooves. In this type of level winding mechanism, an art for limiting torque to be transmitted from the handle shaft to the driven gear has been known (see e.g., U.S. Pat. No. 2,523,134).
The well-known torque limiting device for a fishing reel is mounted on the driven gear. The driven gear is configured to be rotated through an intermediate gear in conjunction with rotation of the spool shaft. The driven gear has an inner member and an outer member. The inner member is configured to be unitarily rotated with the traverse cam shaft (an exemplary shaft member). The outer member is rotatably supported by the inner member. The torque limiting device includes a spring member disposed between the inner member and the outer member. The spring member, having an annular shape, is formed by curving a spring wire rod in a circular shape. The spring member is locked with the inner member. The spring member makes contact with an annular groove formed on the outer member. Torque is limited by the urging force of the spring member.